@m0nhawk: I'm sure that in the answer must also be the constant $e$. The triple sums also involves the hypergeometric function but this shouldn't be a problem, right?
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Chris's sisterJan 21 '13 at 13:21

@Chris'ssister: 1. It was just an assumption why it does not compute nothing. 2. That a function that gives the numerical value of expression, see N.
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m0nhawkJan 21 '13 at 13:24

@m0nhawk: thank you very much for the explanations offered!
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Chris's sisterJan 21 '13 at 13:26

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